Grinding-mill.



No. 744,452. PATENTBD Nov. .17, 1903. Q

I M. F. ABBE.

GRINDING MILL. APPLICATION FILED AUG. 22, 1902.

N0 MODEL. 3 SHEETS-SHEET 1.

N0 MQDEL.

PATENTED NOV. 1 1903.

4 M. F. ABBE.

GRINDING MILL.

APPLICATION PILED AUG. 22. 1902.

3 SHEETS-SHEET 2.

PATENTED NOV. 17, 1903.

M. F. ABBE.

GRINDING MILL.

APPLICATION FILED AUG. 22, 1902- 3 SHEETS SHEET 3.

30 MODEL.

Tu: moans PETERS co. WoYoumQJwAsHmumm n. c.

UNITED STATES iatented November 17, 1 9051.

PATENT OFFICE;

'GRI NDlNG-MILL.

SPECIFICATION forming part of Letters-Patent No. 744,452, dated November 17, 1903. Application filed August 22, 1902. Serial No. 120,638. (No model.)

York, have invented certain new and useful Improvements in Grinding- Mills, of which:

the following is a specification.

This invention relates'to certain improvements in grinding-mills, and more especially to improvements in grinding-mills of that class in'which a stationary grinding-ring is used'in connection with rotary beaters and a screen through which the ground material is conducted off; and the invention consists of a grinding-mill which comprises an exterior casing provided with radial ribs, a pedestal for supporting said casing, a grinding-ring supported on the radial ribs of the casing, a rotary shaft supported in neck and step bearings of the casing and pedestal, respectively, rotary beaters supported on the extremities of radial arms supported on said shaft, a cylindrical screen above the grinding-ring, a cover for said screen having a cylindrical portion at its center extending in downward direction, an annular cover above the radial arms of the beaters having an upwardly-extending portion projecting into the downwardlyextending portion of said screencover, a central feed-hopper, and a cover. for the exterior casing above the cover of the screen.

The invention consists, further, of a stationary grinding-ring, rotary beaters in connection with said grindingring, an annular cover, a cylindrical screen above the grindingring, a cover for the sa'me'having an interior cylindrical portion surrounding a portion of the annular cover, an exterior casing, a closed cover for said casing at some distance from the cover of the screen, so that an interior circulation of air can be established through the screen, the space between the interior and ex terior covers, and through the opening of annular cover to'the grinding-ring, and downwardly extending segmental discharge-funnels circumferentially arranged at the lower portion of said exterior casing; and the invention consists, lastly, of certain details of. construction which will be fully described hereinafter and finally pointed out in the claims.

In the accompanying drawings, Figure .1 represents a sideelevation of my improved grinding-mill. Fig. 2 is avertical central section of the same; and Figs. 3 and 4 are horizontal-sections, respectively, on lines 3 3 and 4 v4, Fig. 2.

Similar letters of reference indicate corresponding parts.

Referring to the drawings, A represents the pedestal of my improved grinding-mill,

which is formedwitlifourlstandards radially 7 arranged around a central portion, said standards being firmly secured to the floor. The

central portion is provided with a vertical socket a, in which is arranged a flanged sleeve iThisrneck-bearing is formed, like the stepbearing of a cylindrical sleeve, with a circumferential flange at its upper end, which flange is bolted to the bottom of the casing B and closed at the upper and lower ends by elastic gaskets g g to keep the bearings free from dust and ground material, as shown clearly in Fig. 2. The casing B is provided with a cover 0, which is bolted to interior lugs c of the casing and which supports at its center a hopper H, through which the material to be ground is fed to the grinding-ring. Be-

,tweenthe ribs B of the casing are arranged segmental openings O,near the circumference .of the casing, from which extend in downward direction segmental funnels F, which are provided with flanges fat their upper ends for being bolted to the casing and which are connected at their-lower ends with pipes F, that discharge the ground material to suitable compartments below the floor.

On the inner portions of the ribs 13 of the casing B is supported a circular grindingplate D. This plate is provided with an annular flan e D havin a frusto-conical inner C J b surface that is furrowed to form the grinding portion (1. At suitable points of its circumference the flange D is provided with lugs cl, to which the upright supportingstraps e for the cylindrical screen E are attached. These straps bend outwardly at their lower ends and inwardly at their upper ends, so as to support the cover E of the screen, said cover being provided with a downwardly -extending cylinder E, that is concentric with the screen. To the shaft S is attached, above the neck-bearing, the hub G of the beater-frame, which is formed of four arms G, provided at their outer ends with steel beaters G attached by countersunk bolts to the arms flush with the face of the same, as shown in Figs. 2 and 3. ()n the beater-arms G is supported an annular cover I, formed with an upwardly-bent contracted portion, which extends somewhat above the lower edge of the interior cylinder E of the screen-cover E. This cover I serves for the purpose of permitting a free circulation of air in the direction of the arrows through the interior cylinder E and the cover I to the grinding-ring D and in upward direction through the screen and the space between the cover C of the exterior casing and the cover E of the screen, so that the current of air produced by the rotating beater-arms circulates continuously in the same course without resorting to the outside atmosphere for relieving the pressure at the grinding-surface. The quick rotation of the beater-arms produces an effective action near the central portion of the grinding-plate and keeps thereby the air in motion, so as to produce the cooling of the grinding-surfaces and prevent any injurious pressure of the air on the operating parts. The face of the heaters is flush with the ends of the beater-arms, so as to produce the free outward sliding and forcing of the material by centrifugal force toward the grinding ring. This is an important feature, as there is no impediment to the flow of material in outward direction, so that it can be acted on efi'feetively by the grindingring and the heaters, which project outwardly and downwardly from the ends of the beaterarms, as shown clearly in Fig. 2.

The step-bearing for the driving-shaft S is formed of a disk-shaped fiber plate I) with convex sides, having a steel disk 8 below the same, with a convex side adjacent to the fiber disk. A tightening-gasket is interposed between the socket a and the bearing of the interior sleeve a of the step-bearing. A screw b is arranged below the lower steel disk, said screw being provided with a jam-nut and lamp-wick gasket b and serving for adjusting the step-bearing, and thereby by the position of the shaft the position of the heaters, so as to provide for the wear of the same. This screw also regulates the distance between the beaters and the grinding-ring, and it has the advantage that convenient access is given to the same, as the attendant can get directly to the space formed between the discharge-funnels and the two adjacent standards, as shown in Fig. 1. The adjustment of the set-screw can therefore be accomplished at any time without removing any parts of the mill. The journals of the shaft at their neck and step bearings are lubricated by any suitable lubricating devices connected With the same. Power is imparted to the shaft by means of .a pulley P, which is keyed to the shaft between the neck and step bearings, said pulley receiving power by a motiontransmitting belt from a suitable drivingshaft.

The grinding-ring D, screen E, and the top plate E form one connected mechanism, which can be taken out from the mill complete by first taking off the top plate C of the exterior casing B and the beater-arms, with the annular cover supported thereon. The entire driving mechanism is thereby not interrupted, so that repairs can be made to these parts without interfering with the driving mechanism.

My improved grinding-mill has the following advantages: First, the casing is s'upported at a suitable height, so that the discharge funnels or spouts are above the floor, so that the ground material can be discharged independently into receiving-chambers directly; second, all the journals of the bearings of the driving-shaft are below the working or grinding parts of the mill, so that it is impossible for any oil to get into the material being ground; third, the grinding ring, screen, beater-arms, and annular cover can be removed independently without interfering with the driving mechanism that is arranged below the same; fourth, by the arrangement of the annular cover on the beater-arms and its relative position to the grinding-ring and screen-cover an effective circulation of airis kept up continuously without any air-inlet; fifth, the exterior casing, discharge-funnels, air-space in the same, and the grinding parts can all be removed independently of the driving mechanism, so that a very compact grinding-mill is obtained in which all the parts are uniformly balanced and conveniently arranged.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. In a grinding-mill,the combination,with a stationary grinding-plate having a circumferential grindin g-rin g, of a cylindrical screen supported on the circumference of said grinding-ring, a cover for the screen provided with a downwardly-extending interior cylindrical portion, rotary beater-arms provided with beaters at their outer ends, an annular cover supported on said beater-arms extending with its upper contracted end upwardly to the inte rior cylindrical portion of the screen-cover, an exterior casing provided with a cover located at some distance above the top of the screencover, and a central hopper in said casingcover for the supply of material to be ground, substantially as set forth.

2. In a grinding-mill, the combination, of a stationary grinding-plate, having a circumferential grinding-disk, lugs at the exterior of the grinding-disk, upright straps attached to said lugs, a cylindrical screen attached to said upright straps, a screen-cover attached to the upper ends of said straps and provided With an interior downwardly-extending cylindrical flange, rotary beater-arms, beaters at the ends of the same, an annular cover supported on the said beater-arms and ex- 

